Video: Facebook's 'Penthouse' Cooling System

This video provides a detailed tour of the "penthouse" cooling system in Facebook's new data center, which uses the upper floor of the building as a large cooling plenum with multiple chambers for cooling, filtering and directing the fresh air used to cool the data center.

Yesterday we got a look inside the server rooms at Facebook's new data center in Oregon in part one of our video tour. Today we present part two, in which Facebook Director of Datacenter Engineering Jay Park provides a detailed overview of the facility's "penthouse" cooling system, which uses the upper floor of the building as a large cooling plenum with multiple chambers for cooling, filtering and directing the fresh air used to cool the data center. This video runs about 12 minutes.

Facebook adopted the two-tier structure seen in several recent designs, which separates the servers and cooling infrastructure and allows for maximum use of floor space for servers. Facebook opted to use the top half of the facility to manage the cooling supply, so that cool air enters the server room from overhead, taking advantage of the natural tendency for cold air to fall and hot air to rise – which eliminates the need to use air pressure to force cool air up through a raised floor.

The air enters the facility through an air grill in the second-floor “penthouse,” with louvers regulating the volume of air. The air passes through a mixing room, where cold outdoor air can be mixed with server exhaust heat to regulate the temperature. The cool air then passes through a series of air filters and a misting chamber where a fine spray is applied to further control the temperature and humidity. The air continues through another filter to absorb the mist, and then through a fan wall that pushes the air through openings in the floor that serve as an air shaft leading into the server area.

This diagram from the Open Compute Project provides a building-level view of the penthouse cooling design in Prineville, showing, the hot air plenum for server waste heat and the server rooms.

A look at the data center design for the new Facebook data center in Prineville, Oregon (click for larger image).